If you want to check if it matched a 0-length string, try
if (length($a))

Altogether, it can be written as:
$a = 1 if not length $a;
or
$a = 1 if length $a != 0;

By the way, you shouldn't use $a and $b as variables. They mean something special to sort.

In reply to Re: if var isnt used by ikegami
in thread if var isnt used by metalfan

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